   "Compute aggregate metrics for an evaluation fold."
   [metrics]
   {:matches (union-matches metrics)
-   :empty? (sequence (map :empty?) metrics) ; FIXME: Needless double iteration.
+   :empties (sequence (map :empty?) metrics) ; FIXME: Needless double iteration.
    :ranks (sequence (map :rank) metrics)})
 
 (defn aggregate-evaluation-metrics

  (let [matches (union-matches metrics)]
    {:catalog-coverage (double (/ (count matches)
                                  bidder-count))
     :prediction-coverage (double (/ (count (filter false? (mapcat :empty? metrics)))
                                     contract-count))
     :ranks (mapcat :ranks metrics)}))

(ns matchmaker-sparql.evaluation.metrics
  (:require [clojure.set :refer [union]]
            [taoensso.timbre :as timbre]))

(defn compute-metrics
  "Compute metrics of `matches` given correct `match`."
